New research shows prenatal exposure to folic acid could reduce risk of psychosis

New research we’ve funded has linked - for the first time - an increase in consumption of folic acid during pregnancy with changes in children’s brain development. And this was associated with a reduction in the incidence of psychotic symptoms.

These findings are an important step forward for research. And they give hope of new opportunities to prevent severe mental illnesses, like schizophrenia, in the future.

Our Director of Research, Dr Sophie Dix explains more:

What’s the issue?

Taking folic acid around the time of conception is known to reduce risk of life-threatening conditions of the nervous system, like spina bifida. This has led 81 countries – including the United States since 1998 – to introduce mandatory folic acid fortification of grain products (such as cereals, bread, pasta and rice). The UK and other European countries do not currently fortify food.

There is also growing evidence that folic acid may have protective benefits for mental illness. For example, research has shown that the development of schizophrenia may be associated with low levels of folic acid and that some people with the condition struggle to process folic acid. But no research has yet found a biological ‘cause’ and ‘effect’.

What did they do?

Dr Joshua Roffman and his team at Harvard University sought to find this evidence. They explored for the first time if exposure to folic acid at the earliest opportunity - when the baby is developing in the womb - could protect the brain against development of psychotic symptoms.

Roffman and colleagues at Massachusetts General Hospital and the University of Pennsylvania studied MRI scans from 1,370 American children age 8 – 18 born prior to, during and after the introduction of fortification in the US. In less than two years fortification had doubled average blood folate levels among women.

They looked at the thickness of the cerebral cortex (the outer layer of cells of the brain), which thins as the brain matures during adolescence. However, if this thinning happens prematurely, at a faster rate, it is a sign of risk of severe mental illness, such as schizophrenia. Roffman found that for children born during or after the introduction of fortification, cortical thinning began much later. This delayed thinning was itself associated with a reduced risk of developing symptoms of psychosis.

What does this mean?

Schizophrenia is a common, devastating condition with lifelong impacts. With no known ways to cure it or prevent it from developing in the first place, there is great need for advances in research. This study is a significant step forward, showing for the first time that prenatal exposure to folic acid alters brain development – in ways that appear to protect against development of psychosis.

It will take roughly a decade to understand whether young people living in countries with grain product fortification have been protected against schizophrenia and other severe mental illnesses.

But the potential of this is huge – with significant policy implications for countries like the UK where fortification doesn’t happen. We’ve all seen the progress that’s possible through public health interventions, from vaccines to fluoridation for tooth decay. This study adds critical biological evidence to the case to prove folic acid’s potential role in preventing severe mental illness.